Radioimmunoassay of cholecystokinin.
Radioimmunoassay of cholecystokinin.
复制标题
胆囊收缩素的放射免疫测定。
DOI：
10.1007/bf02430535
复制
发表时间：
1983
影响因子：
3.1
通讯作者：
Chey,WY
中科院分区：
文献类型：
--
作者：
Chang,TM;Chey,WY
本文报道了一种高灵敏度、高特异性的胆囊收缩素（CCK）放射免疫分析法。用氯胺T催化碘化法制备完全免疫反应性的[125 I] CCK 33，然后用凝胶过滤和离子交换层析纯化。以15%的猪CCK为抗原，经多次免疫家兔，获得了高效价的抗血清。该抗血清对CCK 33和CCK 39具有高度的特异性，40%的结合位点与CCK 80具有高亲和力，但与胃泌素反应较弱。采用XAD-2树脂柱萃取技术消除血浆干扰，CCK回收率高。总体试验灵敏度为3.3 pM，测定的批内和批间变异系数分别为9.6%和20.8%，血浆浓度为11.2 pM。该方法能检测犬血浆中加入的CCK_（33）和CCK_（83）的线性增量，并能检测犬静脉滴注的CCK_（83）的线性增量，最低可达0.03 μg/kg/hr。该检测方法进行了验证，其能力，以监测增加血浆CCK免疫反应性摄入后的肉类在人类和狗，以及以下胃内输注肝提取物餐和十二指肠内输注苯丙氨酸在狗。当CCK-8和胃泌素结合位点的抗血清被去除的免疫吸附，处理后的抗血清仍然能够测量餐后血浆CCK浓度的变化，表明CCK-33样免疫反应存在于血浆中。
A highly sensitive and specific radioimmunoassay for cholecystokinin (CCK) has been developed. Fully immunoreactive [125I]CCK33was prepared by chloramine T-catalyzed iodination followed by purification by gel filtration and ion exchange chromatography. A high titer of antiserum was obtained by multiple immunizations of rabbits with 15% pure porcine CCK without conjugation. The antiserum was highly specific for CCK33and CCK39, with 40% of the binding sites recognizing CCK8at high affinity, but reacted weakly with gastrin. Plasma interference was eliminated by an XAD-2 resin column extraction technique with high recovery of CCK. The overall assay sensitivity was 3.3 pM with intra-and interassay coefficients of variation determined with a plasma of 11.2 pM at 9.6 and 20.8%, respectively. The assay was capable of detecting linear increments of both CCK33and CCK8added into plasma and intravenous infusion of CCK8as low as 0.03 μg/kg/hr in dogs. The assay was validated by its ability to monitor increase of plasma CCK immunoreactivity after ingestion of a meat meal in both humans and dogs, as well as following intragastric infusion of liver extract meal and intraduodenal infusion of phenylalanine in dogs. When the CCK8and gastrin binding sites of the antiserum were removed by immunoadsorption, the treated antiserum remained capable of measuring a postprandial change in plasma CCK concentration, indicating that CCK33-like immunoreactivity was present in the plasma.